RNA based medicine for HIV

A potential RNA based treatment for HIV is showing positive results in tests on mice.

Researchers injected the two component medicine into GM mice engineered to be susceptible to HIV. They found the quantity of the HIV virus in the mouse's blood fell significantly.

The medicine is composed of two different types of RNA. The first, called an aptamer, binds onto a protein on the surface of the HIV virus and neutralises it in the blood. The aptamer also transports the second type of RNA, called small interfering RNA (siRNA) into infected cells. siRNA then blocks the expression of two genes in infected cells that HIV needs to replicate.

When mice were given just the aptamer component of the medicine, levels of virus in the blood were also found to fall. However, the combination of aptamer and siRNA medicine suppressed the virus for a week longer than just the aptamer.

siRNA was also directly found inside target cells and reduced the expression of the two genes HIV needs for replication. However, there remain questions over how widespread the uptake of siRNA into infected cells is.

Patients would need regular injections of the medicine as it is only effective for about a week. The new medicine could help patients who have developed resistance to other HIV drugs.